On Tue, 2018-08-14 at 18:23 +0530, Manikanta Pubbisetty wrote: > > I don't think that makes sense. If we split the capability of AP_VLAN > > and AP_VLAN_FOR_4ADDR at the "root", then we don't need to play with all > > these things. Yes, this is slightly awkward for userspace, and perhaps > > with the interface combination checks, but I'd like you to look at that. > I was working on splitting the 4-addr functionality from AP/VLAN iftype; > I have introduced a new iftype NL80211_IFTYPE_AP_4ADDR and moved the > 4-addr handling from AP/VLAN to this new iftype. But this approach > breaks the backward compatibility with older userspace applications. Yeah ... I'm confused and no longer sure what I was thinking, nor even what we're trying to achieve here... > Since I am completely moving the 4-addr handling to the new type, older > applications which do not understand this new type will simply fail and > 4-addr mode will be completely broken. > > Currently, whenever a 4-addr client attempts a connection, hostapd just > creates a AP/VLAN interface and moves the 4-addr client to the AP/VLAN > iface; there are no other checks. I had no other option other than going > with a new iftype for 4-addr handling. > > Is there a way we can maintain backward compatibility with this > approach? Retaining the 4-addr handling in AP/VLAN and duplicating the > same functionality to the new iftype seems will work but I am not sure > if this is the right approach. I think we have to keep the 4-addr handling in AP_VLAN iftype either way, to not break existing hostapd. We could introduce a separate AP_VLAN_NO_4ADDR and then require updating hostapd to get non-4addr VLAN, but that also seems awkward. Since hostapd doesn't currently check anything... Ok, no, I'm confused now. If we just clear WIPHY_FLAG_4ADDR_AP, don't we get what we want? 4-addr AP_VLAN interfaces would no longer be permitted to be created? johannes
